# list=[1,2,3,2]
# a=list[0]
# for i in list:
#     if i>a:
#         a=i
# print(a)

# print(isinstance(1,int))

# list1=[1,2,3,4,'a',1]
# sum=0
# for i in list1:
#     if isinstance(i,int):
#         sum=sum+i
# print(sum)

# x=5
# for i in range(2,x):
#     if x%i==0:
#         print("不是素数")
#         break
# else:
#     print("是素数")

x=10
sum=0
for i in range(2,x+1):
    for j in range(2,i):
        if i%j==0:
            break
    else:
        sum=sum+1
print(sum)
